Fight those who do not believe in Allah, nor in the latter day, nor do they prohibit what Allah and His Apostle have prohibited, nor follow the religion of truth, out of those who have been given the Book, until they pay the tax in acknowledgment of superiority and they are in a state of subjection. (Sura 9:29)

Jesus Christ, the Son of God, is the Messiah, and He is the Son of God, definitely not the same person as "Hazrat Mahdi" or any other muslim. There is, however, a counterfeit messiah who will rule the world prior to the return of Jesus Christ. He is the Beast 666.